I pulled a pair of Sennheiser HD25-1 II headphones from the Media Lab loading dock a few weeks ago. They've been amazing, except sometimes sound would cut out from the right can. From Instructables I learned the issue was probably from a loose connection, so I started taking it apart.

Tinning the cable leads was easy, but I screwed up removing the little plastic cap that protects the tiny connectors; my pliers caught on the voice coil and tore the tiny magnet wire.

The voicecoil is comprised of insulated red aluminum wire. To reconnect the wire I had to carefully burn off the insulation by holding a soldering iron to it - but not too long! The aluminum disintegrates a fraction of a second after its insulation burns off. It took many retries and precious millimeters of wire to get the process right.

I didn't have enough wire at this point to attempt stripping the other end and soldering them together, so instead I maneuvered the stripped end I had onto the connector itself. and flooded the receptacle with solder.

Not pretty, but it works!

I'll just roll on the vinyl caps and pretend this screwup never happened.